It is currently 23 Feb 2018, 22:19

Close

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

If m and n are positive integers, what is the number of factors of

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Expert Post
Math Revolution GMAT Instructor
User avatar
D
Joined: 16 Aug 2015
Posts: 4908
GPA: 3.82
If m and n are positive integers, what is the number of factors of [#permalink]

Show Tags

New post 10 Mar 2017, 02:15
Expert's post
1
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  25% (medium)

Question Stats:

73% (00:46) correct 27% (01:27) wrong based on 56 sessions

HideShow timer Statistics

If m and n are positive integers, what is the number of factors of \(3^m7^n\)?

A. mn+m+n
B. m-n+1
C. (m-1)(n-1)
D. (m+1)(n+1)
E. mn
[Reveal] Spoiler: OA

_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
Find a 10% off coupon code for GMAT Club members.
“Receive 5 Math Questions & Solutions Daily”
Unlimited Access to over 120 free video lessons - try it yourself
See our Youtube demo

Manager
Manager
avatar
S
Joined: 13 Apr 2010
Posts: 88
Reviews Badge
Re: If m and n are positive integers, what is the number of factors of [#permalink]

Show Tags

New post 10 Mar 2017, 02:26
MathRevolution wrote:
If m and n are positive integers, what is the number of factors of \(3^m7^n\)?

A. mn+m+n
B. m-n+1
C. (m-1)(n-1)
D. (m+1)(n+1)
E. mn



I think , the question should read m and n are prime numbers then only we can get the total factors as (m+1)(n+1) giving answer as D .
Example . 10^2 === > 5^2 . 2^2 giving total factors as 9 (1, 2 , 4, 5 , 10, 20, 25, 50, and 100 ) for 100.
Expert Post
Math Revolution GMAT Instructor
User avatar
D
Joined: 16 Aug 2015
Posts: 4908
GPA: 3.82
Re: If m and n are positive integers, what is the number of factors of [#permalink]

Show Tags

New post 12 Mar 2017, 17:48
==> The number of factors of \(3^m7^n\) becomes (m+1)(n+1).

The answer is D.
Answer:
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
Find a 10% off coupon code for GMAT Club members.
“Receive 5 Math Questions & Solutions Daily”
Unlimited Access to over 120 free video lessons - try it yourself
See our Youtube demo

Manager
Manager
avatar
S
Status: active
Joined: 25 Jan 2016
Posts: 173
Location: India
Concentration: Finance, Entrepreneurship
GPA: 4
WE: Web Development (Computer Software)
Re: If m and n are positive integers, what is the number of factors of [#permalink]

Show Tags

New post 13 Mar 2017, 00:02
The answer is D
no of factors is given by (m+1)(n+1)
Expert Post
Target Test Prep Representative
User avatar
S
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 2016
Re: If m and n are positive integers, what is the number of factors of [#permalink]

Show Tags

New post 15 Mar 2017, 15:33
MathRevolution wrote:
If m and n are positive integers, what is the number of factors of \(3^m7^n\)?

A. mn+m+n
B. m-n+1
C. (m-1)(n-1)
D. (m+1)(n+1)
E. mn


To determine the total number of factors of a particular number, we add 1 to each exponent of the prime factors in the prime factorization of that number and multiply the resulting numbers together. For example, 12 = 2^2 * 3^1; thus 12 has (2 + 1)(1 + 1) = (3)(2) = 6 factors. Here the number is 3^m * 7^n, so it has a total of (m + 1)(n + 1) factors.

Answer: D
_________________

Jeffery Miller
Head of GMAT Instruction

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Re: If m and n are positive integers, what is the number of factors of   [#permalink] 15 Mar 2017, 15:33
Display posts from previous: Sort by

If m and n are positive integers, what is the number of factors of

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.